Iron and steel industry generates substantial amount of inorganic solid wastes namely blast furnace (BF), Linz-Donawitz (LD) slag from the metallurgical process and fly ash from thermal power plant which creates environmental pollution when dumped in open land. In this investigation, BF and LD slag are incorporated in quartz free fly ash based porcelain system and changes in their properties, phase and microstructural evolution were studied. The samples shown very high flexural strength (>50 MPa) in the temperature range of 1200-1300 °C. Appearance of anorthite crystals were observed when feldspar is gradually replaced by BF and LD slag. The body with a combination of BF slag and feldspar possesses the highest strength (90 MPa) due to the presence of mullite grains and fewer fracture origins caused by large difference in the thermal expansion coefficient between the glassy matrix, quartz and anorthite grains during cooling process. Total replacement of feldspar by equal percentage of BF and LD slag resulted formation of almost 100% anorthite grains with distinct change in crystal morphology. A strong pre-stress is produced on the glassy phase that surrounds the anorthite grains by the large difference in thermal expansion coefficient between the glassy phase and anorthite grain.

Removal of Fe(II) and Mn(II) ions from aqueous solution by fungal biosorbent Aspergillus sp. TU-GM14immobilized on Detarium microcarpum matrix was investigated in this study. Effects of biosorption parameters pH, biosorbent concentration, bead size and equilibrium time on Fe(II) and Mn(II) ions sorption were also determined. Equilibrium was attained within in 3 hours while optimum Fe(II) and Mn(II) ions removal was observed at pH 6, 8 mm bead size, 2 g l-1 spore load respectively. Adsorption capacity was described using Langmuir, Freundlich and BET isotherm models. The experimental data fitted best to the Freundlich model (R2 0.992 and 0.996 for Mn(II) and Fe(II) respectively). Favourable surface sorption process was described by Langmuir isotherm for both metals (Qmax 34 and 14 mg g-1 for Mn(II) and Fe(II) ions) while the BET isotherm constant, B, described high metals sorption beyond the biosorbent surface in a multi-layer sorption process (4.8 and 9.0 for Mn(II) and Fe(II) respectively). Results of the study showed that Aspergillus sp. TU-GM14 biosorbent can remove large quantities of Fe(II) and Mn(II) ions from solution in both surface and multi-layer sorption process with Detarium microcarpum acting as a cheap immobilization matrix.

The objective of this study is to elucidate the efficiency of electrosorption on desalination of aqueous NaClsolution using nano-structured carbon aerogel electrodes. The experiments were performed in an electrosorption cell consisting of a pair of carbon aerogel sheets separated by a 0.5cm spacer. The electrosorption performance is investigated with different applied voltages and solution concentrations. It increases with increasing applied voltage, higher concentration gradient and less double-layer overlapping effect. Under the experimental conditions at the optimum applied voltage of 1.2 Volt and initial NaCl concentration 100 - 1000 mg l-1, the electrosorption capacity was found to be 5.20 - 14.22 mg NaCl/g carbon aerogel.Na+ and Cl- ions are electro-absorbed at the electrical double layer without electron transfer redox reactions at anode and cathode. The good electrosorption performance of carbon aerogel electrodes might be attributed to their high specific area, high electrical conductivity, chemical inertness and optimal pore size distribution for the passage and easy movement of ions during electrosorption and electrodesorption. The process is reversible, as the electrode charge/discharge procedure can be repeated innumerable times without any significant loss of salt sorption capacity in all cycles.

This study was aimed to investigate the use of Mustard stalk as a cheap, eco-friendly adsorbent with support matrix for the immobilization of microbial cell and for subsequent removal of
2,4-dichlrophenol(2,4-DCP) from waste water. A comparative batch study between adsorption as well as simultaneous adsorption and biodegradation (SAB) of 2,4-DCP by mustard stalk immobilized Pseudomonas putida MTCC1194 have been studied in conical flask having concentration ranges of
2,4-DCP from 100 to 1000 mg l-1 with adsorbent dose range 1 to 12 g l-1 at pH range 2 to 9 and temperature range 28°C to 35°C, placed in an orbital shaker. The results of the batch studies showed that simultaneous adsorption and biodegradation (SAB) shows the maximum percent (91%) removal of 2,4-DCP as compared to simple adsorption (86 %) at optimum temperature 32 °C of adsorbent dose 10 g l-1, and pH 6 with MSAC having particle size 0.24 mm. The equilibrium data for 2,4-DCP degradation sorbent systems were well fitted with Langmuir isotherm.

In this paper the influence of key meteorological variables in Penman evaporation method was explored. Monthly data over a 16-years period (1993-2008)were used from Thissio-Athens meteorological station. The climatic parameters of surface air temperature, relative humidity, wind speed and sunshine duration were varied in Penman method and the obtained results were compared. Moreover, the investigation of sunshine duration during winter months was thoroughly examined. An open source software (Hydrognomon) was used for this exploration. The analysis showed that: (a) the influence of the meteorological parameters to evaporation is almost linear, (b) the temperature has the greater influence to annual evaporation while the relative humidity, wind speed and sunshine duration follow, and (c) the relationship between sunshine duration and evaporation in a monthly scale is not constant. During the winter months the increase of sunshine duration leads to decrease of evaporation.

The performed analysis could be used to quantify the impact of climatic change on evaporation, to determine the accuracy of predicted evaporation against that obtained from the meteorological instruments, and to investigate the alternative values of several meteorological variables in the case of limited data sets.

The construction of large infrastructure projects such as highways, railroads, landfills, airports, harbours offers great social-economic opportunities for the development of a region; it is also mainly responsible for the deterioration of natural environment in the greater areas where these projects are located. The goal of environmental impact assessment (EIA) that is carried out before the construction of such a project is to propose measures and actions that will limit negative environmental impacts during its construction and operation phases. The common perception is that large scale infrastructure projects can only damage natural environment even though very strict environmental requirements are imposed by the Authorities. This was not the case in Eleonas Attikis region in Greece where METRO facilities were built. During the construction phase, hazardous solid wastes were found buried in the urban area where METRO facilities (station, tunnel and depot) were located, raising serious environmental issues in natural and human environment in the region.

The protection and restoration of environment in an uncontrolled waste dumpsite require accurate estimation of subsurface pollution extent and intensity. The scope of the present analysis is to map the contamination in the aquifer of Eleona Attikis where METRO facilities (station, tunnel and depot) were built. Numerical modelling approaches were used to estimate environmental impacts of this project to soil and water resources in the greater region. The results have shown that the removal of buried solid wastes to construct METRO station and depot was crucial in order to eliminate negative impacts in soil and subsurface water resources. An impact assessment of hazardous solid wastes buried for many years in the aquifer was also performed. The findings of this analysis proved that the implementation of a large infrastructure project such as the one in Eleona Attikis Greece was environmentally beneficial for the region.

This study examines the implication of a market-based system to allocate water regionally in one of the most intensively irrigated areas of Greece. The proposed approach combines elements from administrative allocation and tradable water rights in order to assess several water supply scenarios under growing water scarcity conditions. In this framework, irrigation water demand functions were derived by means of an optimization model that maximizes the expected annual net benefits from water use in agriculture. Then, an inter-district water market model is developed to compute the most effective water allocation at the basin-level. An institutional reform is suggested, that is linked with the creation of effective water users’ associations. The aim of this reform is to achieve a functioning and low-cost trading system at the basin level. The results show that significant volumes of water would be traded under various deficit scenarios, mainly due to the spatial heterogeneity in water use and availability.

Water supply system is a critical infrastructure. Main task of urban water system is to provide consumers with drinking water in adequate quantity, at the required quality and pressure corresponding to current standards.

For the purposes of this paper, operational reliability of the water supply system is defined as the ability to supply a constant flow of water for various groups of consumers, with a specific quality and specific pressure, according to consumers demands, in specific operational conditions, at any or at a specific time.

The main aim of this paper is to present a method for risk analysis using Bayesian process. The proposed method made it possible to estimate risk associated with the possibility of partial or total loss of the ability of water supply system operation. The paper proposes to consider two types of risk: the first type, associated with the possibility of interruptions in water supply and the second type, associated with the possibility of tap water contamination.

In the present study, batch adsorption studies were performed for the removal of malachite green and acid blue 161 dyes from aqueous solutions by varying parameters such as contact time, waste marble dust amount, initial dye concentration and temperature. The equilibrium adsorption data were analyzed by Langmuir, Freundlich and Temkin adsorption isotherm models. The Langmuir and Freundlich adsorption models agree well with experimental data. The pseudo-second order, intraparticle intraparticle diffusion and Elovich kinetic models were applied to the experimental data in order to describe the removal mechanism of dye ions by waste marble dust. The pseudo-second order kinetic was the best fit kinetic model for the experimental data. Thermodynamics parameters such as ΔG, ΔH and ΔS were also calculated for the adsorption processes. The experimental data were used to construct an artificial neural network (ANN) model to predict removal of malachite green and acid blue 161 dyes by waste marble dust. A three-layer ANN, an input layer with four neurons, a hidden layer with 12 neurons, and an output layer with one neuron is constructed. Different training algorithms were tested on the model to obtain the proper weights and bias values for ANN model. The results show that waste marble dust is an efficient sorbent for malachite green dye and ANN network, which is easy to implement and is able to model the batch experimental system.

In this work, three samples of nitrogen-doped TiO2 prepared at different calcination temperatures (400, 450 and 500 °C) were applied for the adsorption of Direct Black 38. Kinetic studies about the adsorption of Direct Black 38 on nitrogen-doped TiO2 were performed under different initial dye concentrations
(75-175 mg l-1). Pseudo-first and pseudo-second order models were fitted with the experimental data. The results revealed that nitrogen-doped TiO2 synthesized at 400 °C presented the more adequate characteristics for adsorption purposes, such as specific surface area of 151 m2 g-1. The adsorption kinetics agreed with the pseudo-second order model, at initial dye concentrations from 75 to 175 mg l-1. The maximum adsorption capacity predicted by the pseudo-second order model was 138.3 mg g-1, and was obtained using nitrogen-doped TiO2 synthesized at 400 °C. In summary, these results revealed that nitrogen-doped TiO2 is a good material for the removal Direct Black 38 from aqueous solutions by adsorption.